学校にいる時間をなるべく短くしたい引っ込み思案の中学生・克久が、学校で最も練習時間の長い吹奏楽部に入部したことで、次第に外の世界を見つめ直し、成長していく姿を描く。

I, a virgin and an ordinary college student, decided to live alone, which was my dream, and I was working on moving house with a friend. As he was carrying his belongings, excited about his new life, Nao, a married woman living next door, called out to him. We exchanged a simple greeting, but my eyes were glued to the protrusion of Nao's chest that was visible through her thin dressing gown, and I don't remember anything about that moment. A few days after thinking about Nao and indulging in masturbation, I ran into Nao, who was dressed like an esthetician, when I went out.